HIV antibody assay that gave false negative results: multicentre collaborative study

Area of Science:

• Medical Diagnostics
• Virology
• Public Health

Background:

• Accurate detection of Human Immunodeficiency Virus (HIV) antibodies is crucial for effective public health strategies.
• Commercial diagnostic kits are widely used for HIV screening in clinical laboratories.
• Monitoring the performance of these kits is essential to ensure diagnostic accuracy and patient safety.

Purpose of the Study:

• To evaluate the incidence and characteristics of false negative results from a specific commercial kit for HIV-1 and HIV-2 antibody detection.
• To assess the real-world performance of the assay in a United Kingdom laboratory setting.

Main Methods:

• Retrospective analysis of patient samples tested between July 1995 and March 1996.
• Retesting of negative and positive samples using an alternative HIV-1 and HIV-2 assay.
• Investigation of serum samples from patients with identified false negative results.

Main Results:

• Out of 24,181 patients tested, seven cases of false negative results were identified using the commercial kit.
• These false negatives occurred across diverse risk groups and HIV-1 subtypes, with four cases showing evidence of recent HIV infection.
• The kit's sensitivity was calculated at 99.2% (497/501), potentially lower when considering all identified false negatives.

Conclusions:

• The commercial kit demonstrated high sensitivity but is not infallible, as evidenced by the identified false negative results.
• The findings highlight the importance of ongoing surveillance and re-evaluation of diagnostic assays for HIV.
• Clinicians should remain aware of potential false negative results, especially in cases of suspected recent HIV infection.